C5a, a 74 amino acid peptide, is generated in the complement cascade by the cleavage of the complement protein C5 by the complement C5 convertase enzyme. C5a has both anaphylatoxic (e.g., bronchoconstricting and vascular spasmogenic) and chemotactic effects. Therefore, it is active in engendering both the vascular and cellular phases of inflammatory responses. Because it is a plasma protein and, therefore, generally almost instantly available at a site of an inciting stimulus, it is a key mediator in terms of initiating the complex series of events that results in augmentation and amplification of an initial inflammatory stimulus. The anaphylatoxic and chemotactic effects of the C5a peptide are believed to be mediated through its interaction with C5a receptor (CD88 antigen), a 52 kD membrane bound G-protein coupled receptor (GPCR). C5a is a potent chemoattractant for polymorphonuclear leukocytes, bringing neutrophils, basophils, eosinophils and monocytes to sites of inflammation and/or cellular injury. C5a is one of the most potent chemotactic agents known for a wide variety of inflammatory cell types. C5a also “primes” or prepares neutrophils for various antibacterial functions (e.g., phagocytosis). Additionally, C5a stimulates the release of inflammatory mediators (e.g., histamines, TNF-α, IL-1, IL-6, IL-8, prostaglandins, and leukotrienes) and the release of lysosomal enzymes and other cytotoxic components from granulocytes. Among its other actions, C5a also promotes the production of activated oxygen radicals and the contraction of smooth muscle.
Considerable experimental evidence implicates increased levels of C5a in a number of autoimmune diseases and inflammatory and related disorders. Agents that block the binding of C5a to its receptor other agents, including inverse agonists, which modulate signal transduction associated with C5a-receptor interactions, can inhibit the pathogenic events, including chemotaxis, associated with anaphylatoxin activity contributing to such inflammatory and autoimmune conditions. The present invention provides such agents, and has further related advantages.
or a pharmaceutically acceptable salt thereof, wherein:    R1 is selected from hydrogen, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted cycloalkenyl, optionally substituted alkoxy, optionally substituted cycloalkoxy, optionally substituted (cycloalkyl)alkoxy, or optionally substituted heterocycloalkyl;    R2 is selected from —XRA, —(CRARB)OR4, —CRARBNR4R5 and —CRARBQ;    R3 is selected from optionally substituted aryl, optionally substituted cycloalkyl, optionally substituted arylalkyl, optionally substituted aryloxy, optionally substituted arylalkoxy, optionally substituted heterocycle, optionally substituted heterocycle-oxy, —O—(CRARB)m—Y, —N(RB)—(CRARB)m—XRA, or —N(RB)—(CRARB)m—Y, wherein said heterocycle is saturated, unsaturated or aromatic and has from 1 to 3 rings and 3 to 7 ring members in each ring;    R4 is:            (i) C2-C8alkyl, C2-C8alkenyl, C2-C8alkynyl, (C3-C7cycloalkyl)C0-C4alkyl, mono- or di-C1-C4alkylamino)C2-C4alkyl, (3- to 7-membered heterocycloalkyl)C0-C4alkyl, arylC0-C4alkyl, or heteroarylC0-4alkyl, each of which is optionally substituted; or        (ii) joined to R5 to form, with the nitrogen to which R4 and R5 are bound, a heterocycle having from 1 to 3 rings, 5 to 7 ring members in each ring, and is optionally substituted;            R5 is:            (i) hydrogen;        (ii) C1-C6alkyl, C2-C6alkenyl, C2-C6alkynyl, (C3-C7carbocycle)C0-C4alkyl, each of which is optionally substituted; or        (iii) joined to R4 to form an optionally substituted heterocycle;            Ar is mono-, di-, or tri-substituted phenyl, optionally substituted naphthyl, or optionally substituted heteroaryl having from 1 to 3 rings, 5 to 7 ring members in each ring;    RA and RB, which may be the same or different, are independently selected at each occurrence from:            (i) hydrogen and hydroxy, and (ii) alkyl groups, cycloalkyl groups, and (cycloalkyl)alkyl groups, each of which is optionally further substituted with one or more substituent(s) independently selected from oxo, hydroxy, halogen, cyano, amino, C1-6alkoxy, mono- or di-(C1-6alkyl)amino, —NHC(═O)(C1-6alkyl), —N(C1-6alkyl)C(═O)(C1-6alkyl), —NHS(O)n(C1-6alkyl), —S(O)n(C1-6alkyl), —S(O)nNH(C1-6alkyl), —S(O)nN(C1-6alkyl)(C1-6alkyl), and Z;            X is independently selected at each occurrence from —CHRB—, —O—, —C(═O)—, —C(═O)O—, —S(O)n—, —NRB—, —C(═O)NRB—, —S(O)nNRB—, —NRBC(═O)—, and —NRBS(O)n—;    Y and Z are independently selected at each occurrence from 3- to 7-membered carbocyclic or heterocyclic groups which are saturated, unsaturated, or aromatic, which are optionally substituted with one or more substituents independently selected from halogen, oxo, hydroxy, amino, cyano, C1-4alkyl, C1-4alkoxy, mono- or di-(C1-4alkyl)amino, and —S(O)n(alkyl);    Q is an optionally substituted carbocyclic or optionally substituted heterocyclic group which are saturated, unsaturated or aromatic and comprises between 3 and 18 ring atoms arranged in 1, 2, or 3 rings which are fused, spiro or coupled by a bond;    m is independently selected at each occurrence from integers ranging from 0 to 8; and    n is an integer independently selected at each occurrence from 0, 1, and 2.
Within certain other aspects, compounds provided herein are 4,5-disubstituted-2-arylpyrimidines of Formula II:
or a pharmaceutically acceptable form thereof, wherein:    Ar is mono-, di-, or tri-substituted phenyl, optionally substituted naphthyl, or optionally substituted heteroaryl having from 1 to 3 rings and 5 to 7 ring members in each ring;    A is OR4, NR4R5, or CR4(XRy)2;    R1 is selected from hydrogen, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted cycloalkenyl, optionally substituted alkoxy, optionally substituted cycloalkoxy, optionally substituted (cycloalkyl)alkoxy, or optionally substituted heterocycloalkyl;    R3 is selected from halogen, amino, cyano, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted alkoxy, optionally substituted cycloalkyloxy, optionally substituted aryl, optionally substituted arylalkyl, optionally substituted aryloxy, optionally substituted arylalkoxy, optionally substituted heterocycle, optionally substituted heterocycle-oxy, -E-(CRCRD)m-Z, or -E-(CRCRD)m—XRA, wherein said heterocycle has from 1 to 3 rings and between 3 and 7 ring members in each ring;    R4 is:            (i) C2-C8alkyl, C2-C8alkenyl, C2-C8alkynyl, (C3-C7cycloalkyl)C0-C4alkyl, mono- or di-(C1-C4alkylamino)C2-C4alkyl, (3- to 7-membered heterocycloalkyl)C0-C4alkyl, arylC0-C4alkyl, or heteroarylC0-4alkyl, each of which is substituted with from 0 to 4 substituents independently chosen from Rx, C2-C4alkanoyl, mono- and di-(C1-C4alkyl)aminoC1-C4alkyl, mono- and di-(C1-C4alkyl)aminoC1-C4alkoxy, (3- to 7-membered heterocycloalkyl)C0-C4alkyl and XRy; or        (ii) joined to R5 to form, with the nitrogen to which R4 and R5 are bound, a heterocycle having from 1 to 3 rings, 5 to 7 ring members in each ring, wherein the heterocycle is substituted with from 0 to 4 substituents independently chosen from Rx, oxo and W-Z;            R5 is:            (i) hydrogen;        (ii) C1-C6alkyl, C2-C6alkenyl, C2-C6alkynyl, (C3-C7carbocycle)C0-C4alkyl, each of which is substituted with from 0 to 3 substituents independently chosen from halogen, hydroxy, amino, cyano, C1-C4alkyl, C1-C4alkoxy, methylamino, dimethylamino, trifluoromethyl and trifluoromethoxy; or        (iii) joined to R4 to form an optionally substituted heterocycle;            R8 and R9 are independently selected from hydrogen, halogen, hydroxy, C1-C6alkyl, C2-C6alkenyl, C2-C6alkynyl, C1-C6alkoxy, C1-C6alkylamino and (C3-C7cycloalkyl)C0-C4alkyl;    E is a single covalent bond, oxygen, or NRA;    X is a single covalent bond, —CRARB—, —O—, —C(═O)—, —C(═O)O—, —S(O)n— or —NRB—; and    Ry is:            (i) hydrogen; or        (ii) C1-C10alkyl, C2-C10alkenyl, C2-C10alkynyl, (C3-C10carbocycle)C0-C4alkyl or (3- to 10-membered heterocycle)C0-C4alkyl, each of which is substituted with from 0 to 6 substituents independently selected from Rx, oxo, —NH(C1-C6alkanoyl), —N(C1-C6alkyl)(C1-C6alkanoyl), —NHS(On)(C1-C6alkyl), —N(S(On)(C1-C6alkyl)2, —S(On)NH(C1-C6alkyl) and —S(On)N(C1-C6alkyl)2;            W is a single covalent bond, —CRARB—, —NRB— or —O—;    Z is independently selected at each occurrence from 3- to 7-membered carbocycles and heterocycles, each of which is substituted with from 0 to 4 substituents independently selected from halogen, oxo, —COOH, hydroxy, amino, cyano, C1-C6alkyl, C1-C6alkoxy, C1-C6haloalkyl, C1-C6haloalkoxy, mono- and di-(C1-C6alkyl)amino, (C1-C6alkyl)(2-acetamide)amino and —S(On)(C1-C6alkyl);    RA and RB are independently selected at each occurrence from:            (i) hydrogen; and        (ii) C1-C10alkyl, C2-C10alkenyl, C2-C10alkynyl, saturated or partially saturated (C3-C10carbocycle)C0-C4alkyl and saturated or partially saturated (3- to 10-membered heterocycle)C0-C4alkyl, each of which is substituted with from 0 to 6 substituents independently selected from oxo, hydroxy, halogen, cyano, amino, C1-C6alkoxy, mono- and di-(C1-C4alkyl)amino, —COOH, —C(═O)NH2, —NHC(═O)(C1-C6alkyl), —N(C1-C6alkyl)C(═O)(C1-C6alkyl), —NHS(On)(C1-C6alkyl), SO3H, —SO2NH2, —S(On)(C1-C6alkyl), —S(On)NH(C1-C6alkyl), —S(On)N(C1-C6alkyl)(C1-C6alkyl) and Z;            RC and RD are independently selected from RA, hydroxy, C1-6alkoxy, and oxo;    Rx is independently chosen at each occurrence from halogen, hydroxy, amino, cyano, nitro, —COOH, —C(═O)NH2, C1-C6alkoxycarbonyl, mono- and di-(C1-6alkyl)aminocarbonyl, C1-C6alkyl, C2-C6alkenyl, C2-C6alkynyl, mono- and di-(C1-C6alkyl)amino, C1-C6alkoxy, C1-C2hydroxyalkyl, C1-C2haloalkyl, C1-C2haloalkoxy, (C3-C7cycloalkyl)C0-C4alkyl, and —S(On)(C1-C6alkyl);    m is an integer independently selected at each occurrence from 0-8; and    n is an integer independently selected at each occurrence from 0, 1 and 2.
Within certain other aspects, compounds provided herein are 4,5-disubstituted-2-arylpyrimidines of Formula IX:
wherein:    Ar is mono-, di-, or tri-substituted phenyl, optionally substituted naphthyl, or optionally substituted heteroaryl, said heteroaryl having from 1 to 3 rings, 5 to 7 ring members in each ring and, in at least one of said rings, from 1 to about 3 heteroatoms selected from N, O, and S;    q is 0, 1 or 2;    A is OR4, NR4R5, or CR4R5XRy;    R1 is selected from hydrogen, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted cycloalkenyl, optionally substituted alkoxy, optionally substituted cycloalkoxy, or optionally substituted (cycloalkyl)alkoxy;    R4 is:            (i) C2-C8alkyl, C2-C8alkenyl, C2-C8alkynyl, (C3-C7cycloalkyl)C0-C4alkyl, mono- or di-(C1-C4alkylamino)C2-C4alkyl, (3- to 7-membered heterocycloalkyl)C0-C4alkyl, phenylC0-C4alkyl, or heteroarylC0-4alkyl, each of which is substituted with from 0 to 4 substituents independently chosen from Rx, C2-C4alkanoyl, mono- and di-(C1-C4alkyl)aminoC1-C4alkyl, mono- and di-(C1-C4alkyl)aminoC1-C4alkoxy, (3- to 7-membered heterocycloalkyl)C0-C4alkyl and XRy; or        (ii) joined to R5 to form, with the nitrogen to which R4 and R5 are bound, a heterocycle having from 1 to 3 rings, 5 to 7 ring members in each ring, and is substituted with from 0 to 4 substituents independently chosen from Rx, oxo and W-Z;            R5 is:            (i) hydrogen;        (ii) C1-C6alkyl, C2-C6alkenyl, C2-C6alkynyl, (C3-C7carbocycle)C0-C4alkyl, each of which is substituted with from 0 to 3 substituents independently chosen from halogen, hydroxy, amino, cyano, C1-C4alkyl, C1-C4alkoxy, methylamino, dimethylamino, trifluoromethyl and trifluoromethoxy; or        (iii) joined to R4 to form an optionally substituted heterocycle;            R8 and R9 are independently selected from hydrogen, halogen, hydroxy, C1-C6alkyl, C2-C6alkenyl, C2-C6alkynyl, C1-C6alkoxy, C1-C6alkylamino and (C3-C7cycloalkyl)C0-C4alkyl;    R13 represents from 0 to 3 substituents independently chosen from:            (i) Rx; and        (ii) phenyl and pyridyl, each of which is substituted with from 0 to 4 substituents independently chosen from halogen, hydroxy, amino, cyano, C1-C4alkyl, C1-C4alkoxy, (C3-C7cycloalkyl)C0-C4alkyl, C1-C2haloalkyl, C1-C2haloalkoxy and mono- and di-(C1-C4alkyl)amino; and            X is a single covalent bond, —CRARB—, —O—, —C(═O)—, —C(═O)O—, —S(O)n— or —NRB—; and    Ry is:            (i) hydrogen; or        (ii) C1-C10alkyl, C2-C10alkenyl, C2-C10alkynyl, C3-C10carbocycleC0-C4alkyl or (3- to 10-membered heterocycle)C0-C4alkyl, each of which is substituted with from 0 to 6 substituents independently selected from Rx, oxo, —NH(C1-C6alkanoyl), —N(C1-C6alkyl)(C1-C6alkanoyl), —NHS(On)(C1-C6alkyl), —N(S(On)(C1-C6alkyl)2, —S(On)NH(C1-C6alkyl) and —S(On)N(C1-C6alkyl)2;            W is a single covalent bond, —CRARB—, —NRB— or —O—;    Z is independently selected at each occurrence from 3- to 7-membered carbocycles and heterocycles, each of which is substituted with from 0 to 4 substituents independently selected from halogen, oxo, —COOH, hydroxy, amino, cyano, C1-C6alkyl, C1-C6alkoxy, C1-C6haloalkyl, C1-C6haloalkoxy, mono- and di-(C1-C6alkyl)amino and —S(On)(C1-C6alkyl); and    RA and RB are independently selected at each occurrence from:            (i) hydrogen; and        (ii) C1-C10alkyl, C2-C10alkenyl, C2-C10alkynyl, saturated or partially saturated (C3-C10carbocycle)C0-C4alkyl and saturated or partially saturated (3- to 10-membered heterocycle)C0-C4alkyl, each of which is substituted with from 0 to 6 substituents independently selected from oxo, hydroxy, halogen, cyano, amino, C1-C6alkoxy, mono- and di-(C1-C4alkyl)amino, —COOH, —C(═O)NH2, —SO2NH2, —NHC(═O)(C1-C6alkyl), —N(C1-C6alkyl)C(═O)(C1-C6alkyl), —NHS(On)(C1-C6alkyl), —S(On)(C1-C6alkyl), —S(On)NH(C1-C6alkyl), —S(On)N(C1-C6alkyl)(C1-C6alkyl) and Z;            RC and RD are independently selected from RA, hydroxy, C1-6alkoxy, and oxo;    Rx is independently chosen at each occurrence from halogen, hydroxy, amino, cyano, nitro, —COOH, —C(═O)NH2, C1-C6alkoxycarbonyl, mono- and di-(C1-6alkyl)aminocarbonyl, C1-C6alkyl, C2-C6alkenyl, C2-C6alkynyl, mono- and di-(C1-C6alkyl)amino, C1-C6alkoxy, C1-C2hydroxyalkyl, C1-C2haloalkyl, C1-C2haloalkoxy, (C3-C7cycloalkyl)C0-C4alkyl, and —S(On)(C1-C6alkyl);    T is CO2H, CONH2, C1-6alkoxycarbonyl, mono- or di-(C1-6alkyl)aminocarbonyl, SO3H, —SO2NH2, or SO2(C1-6alkyl); and    n is an integer independently selected at each occurrence from 0, 1 and 2.
In certain embodiments, C5a receptor modulators provided herein exhibit high affinity for C5a receptor (i.e., an affinity constant for binding to C5a receptor of less than 1 micromolar) or very high affinity for C5a receptor (i.e., an affinity constant for binding to C5a receptor of less than 100 nanomolar). In certain embodiments, such modulators exhibit an affinity for human C5a receptor that is higher than for rat or mouse C5a receptor, preferably at least five times higher, more preferably ten times higher. Affinity of a compound for C5a receptor may be determined, for example, via a radioligand binding assay, such as the assay provided in Example 23.
Within certain aspects, modulators as described herein are C5a receptor antagonists, such as inverse agonists. Certain such compounds exhibit an EC50 of 1 micromolar or less, 500 nM or less, 100 nM or less, or 25 nM or less, in a standard in vitro C5a receptor-mediated chemotaxis assay (such as the assay provided in Example 18) or a calcium mobilization assay (as described in Example 25).
Within further aspects, C5a receptor antagonists are essentially free of C5a receptor agonist activity (i.e., exhibit less than 5% agonist activity in a GTP binding assay as described in Example 24).
The present invention further provides, within other aspects, pharmaceutical compositions comprising at least one C5a receptor modulator as described herein, in combination with a physiologically acceptable carrier or excipient. Processes for preparing such pharmaceutical compositions are also provided. Such compositions are particularly useful in the treatment of C5a-mediated inflammation, such as inflammation associated with various inflammatory and immune system disorders.
Within further aspects, methods are provided for inhibiting signal-transducing activity of a cellular C5a receptor, comprising contacting a cell expressing a C5a receptor with at least one C5a receptor modulator as described herein, and thereby reducing signal transduction by the C5a receptor.
Methods are further provided for inhibiting binding of C5a to C5a receptor in vitro, comprising contacting C5a receptor with at least one C5a receptor modulator as described herein, under conditions and in an amount sufficient to detectably inhibit C5a binding to C5a receptor.
The present invention further provides methods for inhibiting binding of C5a to C5a receptor in a human patient, comprising contacting cells expressing C5a receptor with at least one C5a receptor modulator as described herein.
Within further aspects, the present invention provides methods for treating a patient in need of anti-inflammatory treatment or immunomodulatory treatment. Such methods generally comprise administering to the patient a therapeutically effective amount of a C5a receptor modulator as described herein. Treatment of humans, domesticated companion animals (pets) or livestock animals suffering such conditions is contemplated by the present invention. In certain such aspects, methods are provided for treating a patient suffering from cystic fibrosis, rheumatoid arthritis, psoriasis, cardiovascular disease, reperfusion injury, or bronchial asthma comprising administering to the patient a therapeutically effective amount of a C5a receptor modulator as described herein. In further such aspects, methods are provided for treating a patient suffering from stroke, myocardial infarction, atherosclerosis, ischemic heart disease, or ischemia-reperfusion injury comprising administering to the patient a therapeutically effective amount of a C5a receptor modulator as described herein.
The present invention further provides methods for inhibiting C5a receptor-mediated cellular chemotaxis (preferably leukocyte (e.g., neutrophil) chemotaxis), comprising contacting mammalian white blood cells with a therapeutically effective amount of a C5a receptor modulator as described herein. In certain embodiments, the white blood cells are primate white blood cells, such as human white blood cells.
Within further aspects, the present invention provides methods for using a C5a receptor modulator as described herein as a probe for the localization of receptors, particularly C5a receptors. Such localization may be achieved, for example, in tissue sections (e.g., via autoradiography) or in vivo (e.g., via positron emission tomography, PET, or single positron emission computed tomography, SPECT, scanning and imaging). Within certain such aspects, the present invention provides methods for localizing C5a receptors in a tissue sample, comprising: (a) contacting the tissue sample containing C5a receptors with a detectably labeled compound as described herein under conditions that permit binding of the compound to C5a receptors; and (b) detecting the bound compound. Such methods may, optionally, further comprise a step of washing the contacted tissue sample, prior to detection. Suitable detectable labels include, for example, radiolabels such as 125I, tritium, 14C, 32P and 99Tc.
The present invention also provides packaged pharmaceutical preparations, comprising: (a) a pharmaceutical composition as described herein in a container; and (b) instructions for using the composition to treat a patient suffering from one or more conditions responsive to C5a receptor modulation, such as rheumatoid arthritis, psoriasis, cardiovascular disease, reperfusion injury, bronchial asthma, stroke, myocardial infarction, atherosclerosis, ischemic heart disease, or ischemia-reperfusion injury.
In yet another aspect, the present invention provides methods for preparing the compounds disclosed herein, including the intermediates.
These and other aspects of the present invention will become apparent upon reference to the following detailed description.